Biorheology - Volume 45, issue 3-4

Authors: de Isla, N.G. | Stoltz, J.F.

Article Type: Research Article

Abstract: Osteoarthritis (OA) is a progressive joint disease which represents a combination of several disorders leading to cartilage degradation. The main characteristic of OA is an imbalance between chondrocyte anabolic and catabolic activities. Cytokines produced by the synovium and chondrocytes, especially interleukin 1β (IL-1β) and tumor necrosis factor alpha (TNF-α), play a significant role in the degradation of cartilage. They stimulate the production of nitric oxide (NO), which is involved in cartilage catabolism and also may induce the apoptosis of chondrocytes. The IL-1β produced in activated chondrocytes or synovium may modulate disease progression in OA and should therefore be considered a …potential target for therapeutic interventions. Drug and non-drug treatments are used to relieve pain and/or swelling in OA. Diacerein is a slow-acting drug that may slow down the breakdown of cartilage and relieve pain and swelling. It is not clear whether diacerein works but it has been proposed that diacerein acts as a symptom-modifying and perhaps disease-structure modifying drug. Show more

Keywords: Cartilage, osteoarthritis, diacerein, interleukin-1

DOI: 10.3233/BIR-2008-0503

Citation: Biorheology, vol. 45, no. 3-4, pp. 433-438, 2008

Authors: Deffaud, J. | Kirchmeyer, M. | Domagala, F. | Ficheux, H. | Netter, P. | Bianchi, A. | Jouzeau, J.-Y.

Article Type: Research Article

Abstract: The present work aimed to take advantage of the screening capacity of protein arrays to search for additional targets of rhein in interleukin (IL)-1-stimulated chondrocytes. Primary cultures of chondrocytes from osteoarthritic (OA) patients were stimulated for 24 and 48 h with 1 ng/ml of IL-1α, in the presence or absence of 10−5 M of rhein. Culture supernatants were analyzed with arrays membranes consisting of 120 antibodies directed against cytokines, chemokines, and angiogenic or growth factors and were controlled for 8 proteins by specific immuno-enzymatic assays (ELISA). Protein arrays showed that several CC or CXC chemokines, the growth factor GM-CSF, …the cytokines IL-6, IL-7 and IL-10 (but unexpectedly not IL-1β or TNFα) and the adhesion molecule ICAM-1 were induced maximally by IL-1α. In IL-1-stimulated chondrocytes, rhein reduced slightly the production of MCP-1 and increased those of IL-1Ra, of the cytokine receptors sgp130, IL-6R, sTNFR I and R II, but also of some chemokines or ICAM-1. Specific ELISAs confirmed the effect of rhein on MCP-1, IL-1Ra, sgp130, IL-6R and sTNFR II but was discrepant for GROα and were always more sensitive than protein arrays to detect IL-1 effects such as IL-1Ra and TNFα release. The present data show that rhein modulated some IL-1-induced responses contributing possibly to its chondroprotective (IL-1Ra, MCP-1) or cytokine modifying (sTNFR II, sgp130) properties, but that protein arrays were poorly sensitive to check for IL-1- and/or rhein-induced changes. Show more

Keywords: Rhein, osteoarthritis, cartilage, protein screening, pro-inflammatory cytokines, chemokines

DOI: 10.3233/BIR-2008-0484

Citation: Biorheology, vol. 45, no. 3-4, pp. 439-455, 2008

Authors: De Croos, J.N.A. | Pilliar, R.M. | Kandel, R.A.

Article Type: Research Article

Abstract: Generating bioengineered cartilage yields tissue with physical qualities inferior to that of native tissue. Application of cyclic compression (30 min, 1 kPa, 1 Hz) to cartilage cells (chondrocytes) seeded on calcium polyphosphate substrates significantly increases the accumulation of collagens and proteoglycans by 24 hours, thus improving the tissue generated. The mechanism for this increase is not fully known but seems to follow a remodeling pathway of sequential catabolic and anabolic changes. The initial catabolic event involves increased transcription of matrix metalloproteinase (MMP)-3 and MMP-13 two hours after the end of cyclic compression. As MMP-3 and MMP-13 promoters contain activating protein-1 …(AP-1) DNA binding sites, we investigated the effect of inhibiting DNA binding through the use of modified decoy oligodeoxynucleotides (ODN). Mechanical stimulation in the presence of the ODN blocked AP-1 DNA binding as detected by electrophoretic mobility shift assay and prevented the increased transcription of MMP-3 and MMP-13. As well the increased accumulation of collagens and proteoglycans by 24 hours in mechanically stimulated samples was prevented. The data suggests that the mechano-induction of MMP-3 and MMP-13 may be regulated at the AP-1 DNA binding site and that upregulation of these metalloproteases is a necessary component of the matrix remodeling initiated by cyclic compression. Show more

Keywords: Mechanical stimulation, decoy oligodeoxynucleotides, chondrocytes, tissue engineering

DOI: 10.3233/BIR-2008-0488

Citation: Biorheology, vol. 45, no. 3-4, pp. 459-469, 2008

Authors: Raimondi, Manuela T. | Candiani, Gabriele | Cabras, Mariasara | Cioffi, Margherita | Laganà, Katia | Moretti, Matteo | Pietrabissa, Riccardo

Article Type: Research Article

Abstract: We have studied an in vitro engineered cartilage model, consisting of bovine articular chondrocytes seeded on micro-porous scaffolds and perfused with very low regimens of interstitial flow. Our previous findings suggested that synthesis of sulphated glycosaminoglycans (sGAG) was promoted in this model, if the level of shear generated on cells was maintained below 10 mPa (0.1 dyn/cm2 ). Constructs were stimulated with a median shear stress of 1.2 and 6.7 mPa using two independent culture chambers. Quantification of the applied stresses and of oxygen consumption rates was obtained from computational modelling. Experimentally, we set a time zero reference at 24 …hours after cell seeding and total culture time at two weeks. The cell metabolic activity, measured by MTT, was significantly lower in all constructs at two weeks (−73% in static controls, −66% in the 1.2 mPa group and −60% in the 6.7 mPa group) vs. the time zero group, and significantly higher (+33%) in the 7 mPa group vs. static controls. The ratio between synthesis of collagen type II/type I, measured by Western Blot, was significantly higher in the 1.2 mPa constructs (+109% vs. the 6.7 mPa group, +120% vs. the time zero group and +286% vs. static controls). A trend of decreased α-actin expression was observed with increased ratio of type II to type I collagen, in all groups. These results reinforce the notion that, at early time points in culture, hydrodynamic shear below 10 mPa may promote formation of extra-cellular matrix specific to hyaline cartilage in chondrocyte-seeded constructs. Show more

Keywords: Tissue engineering, cartilage, mechanobiology, shear, oxygen, perfusion, porous scaffold

DOI: 10.3233/BIR-2008-0490

Citation: Biorheology, vol. 45, no. 3-4, pp. 471-478, 2008

Authors: Elder, Steven H. | Shim, Joon Wan | Borazjani, Ali | Robertson, Hess M. | Smith, Kathryn E. | Warnock, James N.

Article Type: Research Article

Abstract: Undifferentiated connective tissue that arises during embryonic development and some healing processes contains pluripotent mesenchymal stem cells. It is becoming increasingly evident that the mechanical environment is an important differentiation factor for these cells. In our laboratory, we have focused on the potential for mechanical signals to induce chondrogenic differentiation of mesenchymal stem cells. Using C3H10T1/2 cells as a model, we have investigated the influence of hydrostatic pressure, equibiaxial contraction, and centrifugal pressure on chondroinduction. Cells responded to cyclic hydrostatic compression (5 MPa at 1 Hz) and cyclic contractile strain (15% at 1 Hz) by upregulating aggrecan and collagen type …II gene expression. In addition, a preliminary study of the effects of centrifugal pressure (4.1 MPa for 30 min) suggests that it may increase cell proliferation and stimulate proteoglycan and collagen type II production. We speculate that compression, whether it is distortional or hydrostatic in nature, applied to undifferentiated connective tissue triggers differentiation toward a chondrocyte-like phenotype and production of a less permeable extracellular matrix which is capable of sustaining increasingly higher hydrostatic fluid pressure for compressive load support. Show more

Keywords: Mesenchymal stem cells, chondrogenic differentiation, hydrostatic pressure, equibiaxial contraction, centrifugal pressure

DOI: 10.3233/BIR-2008-0496

Citation: Biorheology, vol. 45, no. 3-4, pp. 479-486, 2008

Authors: McNulty, Amy L. | Guilak, Farshid

Article Type: Research Article

Abstract: Current therapies for meniscal injury seek to preserve and repair damaged tissue since loss of meniscal tissue is associated with degenerative changes in the joint, ultimately leading to osteoarthritis (OA). After a meniscal tear, the difficulty of integrating juxtaposed meniscal surfaces continues to be an obstacle. In order to determine the local factors that are necessary for successful tissue repair, previous studies have developed in vitro model systems that allow both biological and quantitative biomechanical measures of meniscus repair. Many studies have shown the importance of individual factors in meniscus metabolism, but there is a complex interplay among a variety …of factors that influence meniscal healing, including inflammatory cytokines, growth factors, mechanical loading, and zonal differences in cell and tissue properties. In particular, the upregulation of inflammatory cytokines following joint injury appears to have significant catabolic influences on meniscal cell metabolic activity that must be overcome in order to promote repair. In the presence of inflammatory cytokines, such as interleukin-1 (IL-1) or tumor necrosis factor alpha (TNF-α), intrinsic meniscal repair in vitro is significantly inhibited. While anabolic growth factors, such as transforming growth factor-β1 (TGF-β1), enhance meniscal repair, they cannot completely overcome the IL-1-mediated inhibition of repair. The mechanisms by which these mediators influence meniscal repair, and their interactions with other factors in the microenvironment, such as mechanical loading, remain to be determined. Future studies must address these complex interactions during meniscal healing to ultimately enhance meniscal repair. Show more

Keywords: Articular cartilage, matrix metalloproteinases, fibrochondrocyte, cell migration, meniscectomy, mechanical compression

DOI: 10.3233/BIR-2008-0489

Citation: Biorheology, vol. 45, no. 3-4, pp. 487-500, 2008

Authors: Moutos, Franklin T. | Guilak, Farshid

Article Type: Research Article

Abstract: Tissue engineering remains a promising therapeutic strategy for the repair or regeneration of diseased or damaged tissues. Previous approaches have typically focused on combining cells and bioactive molecules (e.g., growth factors, cytokines and DNA fragments) with a biomaterial scaffold that functions as a template to control the geometry of the newly formed tissue, while facilitating the attachment, proliferation, and differentiation of embedded cells. Biomaterial scaffolds also play a crucial role in determining the functional properties of engineered tissues, including biomechanical characteristics such as inhomogeneity, anisotropy, nonlinearity or viscoelasticity. While single-phase, homogeneous materials have been used extensively to create numerous types …of tissue constructs, there continue to be significant challenges in the development of scaffolds that can provide the functional properties of load-bearing tissues such as articular cartilage. In an attempt to create more complex scaffolds that promote the regeneration of functional engineered tissues, composite scaffolds comprising two or more distinct materials have been developed. This paper reviews various studies on the development and testing of composite scaffolds for the tissue engineering of articular cartilage, using techniques such as embedded fibers and textiles for reinforcement, embedded solid structures, multi-layered designs, or three-dimensionally woven composite materials. In many cases, the use of composite scaffolds can provide unique biomechanical and biological properties for the development of functional tissue engineering scaffolds. Show more

Keywords: Articular cartilage, tissue engineering, stem cell, hydrogel, fiber, biomaterial

DOI: 10.3233/BIR-2008-0491

Citation: Biorheology, vol. 45, no. 3-4, pp. 501-512, 2008

Authors: Cournil-Henrionnet, Christel | Huselstein, Céline | Wang, Yun | Galois, Laurent | Mainard, Didier | Decot, Véronique | Netter, Patrick | Stoltz, Jean-François | Muller, Sylvaine | Gillet, Pierre | Watrin-Pinzano, Astrid

Article Type: Research Article

Abstract: Both chondrocytes and mensenchymal stem cells (MSCs) are the most used cell sources for cartilage tissue engineering. However, monolayer expansion to obtain sufficient cells leads to a rapid chondrocyte dedifferentiation and a subsequent ancillary reduced ability of MSCs to differentiate into chondrocytes, thus limiting their application in cartilage repair. The aim of this study was to investigate the influence of the monolayer expansion on the immunophenotype and the gene expression profile of both cell types, and to find the appropriate compromise between monolayer expansion and the remaining chondrogenic characteristics. To this end, human chondrocytes, isolated enzymatically from femoral head slice, …and human MSCs, derived from bone marrow, were maintained in monolayer culture up to passage 5. The respective expressions of cell surface markers (CD34, CD45, CD73, CD90, CD105, CD166) and several chondrogenic-related genes for each passage (P0–P5) of those cells were then analyzed using flow cytometry and quantitative real-time PCR, respectively. Flow cytometry analyses showed that, during the monolayer expansion, some qualitative and quantitative regulations occur for the expression of cell surface markers. A rapid increase in mRNA expression of type 1 collagen occurs whereas a significant decrease of type 2 collagen and Sox 9 was observed in chondrocytes through the successive passages. On the other hand, the expansion did not induced obvious change in MSCs gene expression. In conclusion, our results suggest that passage 1 might be the up-limit for chondrocytes in order to achieve their subsequent redifferentiation in 3D scaffold. Nevertheless, MSCs could be expanded in monolayer until passage 5 without loosing their undifferentiated phenotypes. Show more

Keywords: Human mesenchymal stem cells, bone marrow, chondrocytes, cartilage engineering, gene expression, flow cytometry

DOI: 10.3233/BIR-2008-0487

Citation: Biorheology, vol. 45, no. 3-4, pp. 513-526, 2008

Authors: Wang, Y. | De Isla, N. | Decot, V. | Marchal, L. | Cauchois, G. | Huselstein, C. | Muller, S. | Wang, B.H. | Netter, P. | Stoltz, J.F.

Article Type: Research Article

Abstract: To investigate whether the chondrocytes–alginate construct properties, such as cell seeding density and alginate concentration might affect the redifferentiation, dedifferentiated rat articular chondrocytes were encapsulated at low density (LD: 3×106 cells/ml) or high density (HD: 10×106 cells/ml) in two different concentrations of alginate gel (1.2% or 2%, w/v) to induce redifferentiation. Cell viability and cell proliferation of LD culture was higher than those of HD culture. The increase in alginate gel concentration did not make an obvious difference in cell viability, but reduced cell proliferation rate accompanied with the decrease of cell population in S phase and G2/M …phase. Scan electron microscopy observation revealed that chondrocytes maintained round in shape and several direct cell–cell contacts were noted in HD culture. In addition, more extracellular matrix was observed in the pericellular region of chondrocytes in 2% alginate culture than those in 1.2% alginate culture. The same tendency was found for the synthesis of collagen type II. No noticeable expression of collagen type I was detected in all constructs at the end of 28-day cultures. These results suggested that construct properties play an important role in the process of chondrocytes' redifferentiation and should be considered for creating of an appropriate engineered articular cartilage. Show more

Keywords: Cell seeding density, alginate, redifferentiation, chondrocytes, tissue engineering

DOI: 10.3233/BIR-2008-0493

Citation: Biorheology, vol. 45, no. 3-4, pp. 527-538, 2008

Authors: Tiitu, V. | Pulkkinen, H.J. | Valonen, P. | Pulliainen, O. | Kellomäki, M. | Lammi, M.J. | Kiviranta, I.

Article Type: Research Article

Abstract: In the present study bovine chondrocytes were cultured in two different environments (static flasks and bioreactor) in knitted poly-L,D-lactide (PLDLA) scaffolds up to 4 weeks. Chondrocyte viability was assessed by employing cell viability fluorescence markers. The cells were visualized using confocal laser scanning microscopy and scanning electron microscopy. The mechanical properties and uronic acid contents of the scaffolds were tested. Our results showed that cultivation in a bioreactor improved the growth and viability of the chondrocytes in the PLDLA scaffolds. Cells were observed both on and in between the fibrils of scaffold. Furthermore, chondrocytes cultured in the bioreactor, regained …their original round phenotypes, whereas those in the static flask culture were flattened in shape. Confocal microscopy revealed that chondrocytes from the bioreactor were attached on both sides of the scaffold and sustained viability better during the culture period. Uronic acid contents of the scaffolds, cultured in bioreactor, were significantly higher than in those cultured in static flasks for 4 weeks. In summary, our data suggests that the bioreactor is superior over the static flask culture when culturing chondrocytes in knitted PLDLA scaffold. Show more

Keywords: Biomaterials, bioreactor, chondrocyte, polylactic acid, tissue engineering

DOI: 10.3233/BIR-2008-0492

Citation: Biorheology, vol. 45, no. 3-4, pp. 539-546, 2008